User manual
 

Dialog Box for Timing Settings

The Timing dialog box provides a user-friendly interface for the settings of the component timing features. When you click the button of a timing item in the Component Inspector, the Timing dialog box is displayed.

Before you start to edit component timing you should set:
  • Target CPU in the Project Panel
  • Used peripherals in the component's properties
  • Supported speed modes in the component's properties

The settings are instantly validated according to the Processor Expert timing model. For details on the timing settings principles please see the chapter .

Timing Dialog Box Controls


Figure 1 - Timing Settings Dialog

Runtime setting configuration

Note: Runtime setting cannot be selected in the BASIC view mode.

Runtime setting type selection determines how the timing setting can be modified at runtime. The following options are available:

  • fixed value - Timing cannot be changed at runtime.
  • from a list of values - Allows to change the timing by selecting one of predefined values (from the list) using component method "SetXXXMode". This method sets the value(s) corresponding to the selected timing into the appropriate prescaler and other peripheral register(s). The values (modes) in the list can be added/removed by editing the timing values table.
  • from interval - Allows to change a timing freely within a selected interval, while all values of the interval are selected with specified precision. Prescaler value is fixed in this mode, timing is set only using compare/reload registers value. It means that it has to be possible to reach all values within the interval by using the same prescaler.
    Please note that this kind of runtime setting requires runtime computations that can be time and space consuming and may not be supported on all microcontrollers.

Note: Some of the methods used for runtime setting of timing will be enabled only if the appropriate runtime setting type is selected.

Timing values table

This table allows to set or modify a requested value(s) for the configured timing. Each row represents one time value and the number of rows depends on the selected type of runtime setting.

  • For the option "fixed value", there is only one row (Init.Value) containing the fixed initialization value.
  • For the option "from a list of values", there is one row for each of the possible timing modes. It is possible to enter 16 possible values (modes). The empty fields are ignored. The user can drag and drop rows within the table to change their order. Please see the section Runtime setting configuration within this chapter for more information.
  • For the option "from interval", the table has three rows that contain the Initial value, low limit and high limit of the interval. Please see the section Runtime setting configuration within this chapter for details on this type of runtime setting.
There are two editable columns:
  • Value - Fill in a requested time value (without units). The drop-down arrow button allows to display a list of neighboring values and the user can select one of them. There is also possible to set the value by double-clicking on a value from the possible settings table (see below).
  • Units - Time units for the value.

Timing precision configuration

It is possible to specify desired precision of the timer settings by using one of the following settings (which one is used depends on the type of the timing) :

  • The field Error allowed allows to specify a tolerated difference between the real timing and the requested value. The Unit field allows to specify the units for the error allowed field (time units or a percentage of the requested value).
  • The Min. resolution field is used for setting interval or capture component timing. Allows the user to specify maximal acceptable length of one tick of the timer.
    In the case of interval settings type, the % of low limit (percentage of the low limit value) can be used as the unit for this value.

Minimal timer ticks

Note: This item is available only for setting of period in components where it's meaningful, for example PWM, PPG.

This item allows to set a minimal number of timer-ticks in period. It means that it will be possible to set a duty of the output signal to at least the specified number of distinct values for any period of the output signal at runtime. Value 0 means no requirements for the timer settings.

Adjusted values

This table displays a real values for each speed mode the currently selected row in the Timing values table. These values are computed from the chosen on-chip peripheral settings, selected prescaler(s) value and the difference between a value selected by the user and the real value.

Status box

The status box displays a status of the timing setting(s). If the timing requirements are impossible to meet, a red error message is displayed, otherwise it's blank and gray.

Possible settings table

This table is displayed on the right side of the timing dialog box when you click the Possible settings button on the top. The table shows values supported by the target CPU for the selected peripheral.

If there are only individual values available to set, the table contains a list of values - each row represents one value. If there are intervals with a constant step available, each row contains one of the intervals with three values: From, Till - minimum and maximum value, Step - a step between values within the interval.

The way the values are displayed may be dependent on

  • Runtime setting type - If it's "fixed value" or "from list of values" — the values present in more rows (overlapping intervals) are shown only once. If the "from time interval" runtime setting type is used, all intervals that can be set by various prescalers combinations are shown, even if they overlap. It's because intervals can differ in resolution, that is number of individual timing steps that can be achieved within them.
  • Timing unit - If a frequency unit is used (e.g. Hz, kHz), the step column is not visible

By clicking on the table header, there is possible to order the rows as per selected column. By clicking the same column again, the user can arrange the rows in ascending or descending order.
Double clicking on a value will place the value into the currently edited row within the Timing values table.

The values listed in the possible settings table depend on the following timing settings:

  • prescalers
  • minimal timer ticks
and it also depend on
  • selected CPU
  • selected peripheral
  • speed-modes enabled for the component

The table contains a speed mode tabs (speed modes and related settings are supported only in the EXPERT view mode) that allow to filter the displayed intervals for a specific speed mode or show intersection of all. Please note that the intersection contains only a values that can be set in all speed modes with absolute precision (without any error), so some values that are still valid due to non-zero Error allowed value are not shown.